Insurance premiums rose at the beginning of the year when the Financial Conduct Authority, the City watchdog, banned the so-called “loyalty penalty”, preventing insurers from offering cheaper deals to new customers at the expense of those renewing their policies.

Louise O’Shea of Confused.com, a comparison website, said: “The main reason car insurance costs are starting to increase is that we’re driving a lot more now than we were 12 months ago. This means the number of claims that insurers are paying out on is likely to have increased too.

“It’s worrying that so many people believed the pricing changes that came into effect in January would guarantee them a lower price, and I have no doubt they had quite a shock when they received their renewal notice and it was higher.”

Costs vary according to where you live. Drivers in inner London pay the most for their insurance, at £864 a year on average, according to ­Confused.com, while motorists in the Scottish Borders pay £370.

Older drivers have been disproportionately stung by higher car insurance costs, with premiums for the over-50s rising faster than in any other age group. Prices for older drivers have risen by 6.2pc in the past three months, according to Consumer Intelligence, while motorists aged 25 to 49 saw increases of 4.1pc. Meanwhile, average premiums for the under-25s fell by 2.3pc.

Ms O’Shea added: “It’s very likely there will be another insurer that can offer a better price for the cover you need, so it is essential to shop around.”